Switcheroo

Exchange control of two target creatures.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Infernal Grasp

Destroy target creature. You lose 2 life.

Demonic Taskmaster

Flying
At the beginning of your upkeep, sacrifice a creature other than Demonic Taskmaster.

Keiga, the Tide Star

Flying
When Keiga, the Tide Star dies, gain control of target creature.

Blue Sun's Twilight

Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Archfiend of the Dross

Flying
Archfiend of the Dross enters the battlefield with four oil counters on it.
At the beginning of your upkeep, remove an oil counter from Archfiend of the Dross. Then if it has no oil counters on it, you lose the game.
Whenever a creature an opponent controls dies, its controller loses 2 life.

Spawnbroker

When Spawnbroker enters the battlefield, you may exchange control of target creature you control and target creature with power less than or equal to that creature's power an opponent controls.

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Vraska, Betrayal's Sting

Compleated ({B/P} can be paid with {B} or 2 life. If life was paid, this planeswalker enters with two fewer loyalty counters.)
0: You draw a card and you lose 1 life. Proliferate.
−2: Target creature becomes a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color" and loses all other card types and abilities.
−9: If target player has fewer than nine poison counters, they get a number of poison counters equal to the difference.

Vow of Torment

Enchant creature
Enchanted creature gets +2/+2, has menace, and can't attack you or planeswalkers you control. (It can't be blocked except by two or more creatures.)

Flesh Reaver

Whenever Flesh Reaver deals damage to a creature or opponent, Flesh Reaver deals that much damage to you.

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Jon Irenicus, Shattered One

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.)
Whenever a creature you own but don't control attacks, you draw a card.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Mass Manipulation

Gain control of X target creatures and/or planeswalkers.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters the battlefield, draw a card.

Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.

Counterspell

Ertai Resurrected

Flash
When Ertai Resurrected enters the battlefield, choose up to one —
• Counter target spell, activated ability, or triggered ability. Its controller draws a card.
• Destroy another target creature or planeswalker. Its controller draws a card.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Painwracker Oni

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
At the beginning of your upkeep, sacrifice a creature if you don't control an Ogre.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Greater Harvester

At the beginning of your upkeep, sacrifice a permanent.
Whenever Greater Harvester deals combat damage to a player, that player sacrifices two permanents.

Dragonlord Silumgar

Flying, deathtouch
When Dragonlord Silumgar enters the battlefield, gain control of target creature or planeswalker for as long as you control Dragonlord Silumgar.

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Rotting Regisaur

At the beginning of your upkeep, discard a card.

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Go for the Throat

Ashiok, Sculptor of Fears

+2: Draw a card. Each player mills two cards.
−5: Put target creature card from a graveyard onto the battlefield under your control.
−11: Gain control of all creatures target opponent controls.

Jace, Ingenious Mind-Mage

+1: Draw a card.
+1: Untap all creatures you control.
−9: Gain control of up to three target creatures.

Entrancing Melody

Gain control of target creature with mana value X.

Rite of Belzenlok

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create two 0/1 black Cleric creature tokens.
III — Create a 6/6 black Demon creature token with flying, trample, and "At the beginning of your upkeep, sacrifice another creature. If you can't, this creature deals 6 damage to you."

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Exchange of Words

When Exchange of Words enters the battlefield, choose two target creatures. For as long as Exchange of Words remains on the battlefield, exchange the text boxes of those creatures.

Vow of Malice

Enchant creature
Enchanted creature gets +2/+2, has intimidate, and can't attack you or planeswalkers you control. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Vow of Flight

Enchant creature
Enchanted creature gets +2/+2, has flying, and can't attack you or planeswalkers you control.

Steel Golem

Parasitic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

Cytoplast Manipulator

Graft 2 (This creature enters the battlefield with two +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{U}, {T}: Gain control of target creature with a +1/+1 counter on it for as long as Cytoplast Manipulator remains on the battlefield.

Corrupted Conscience

Enchant creature
You control enchanted creature.
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)